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#1
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OT - outdoor amber LED flood lights?
I know this is completely OT, but I was just wondering if anyone has ever
been able to find any outdoor, dusk to dawn, amber colored LED flood lights (and fixtures), as I can't seem to find any listed anywhere. They would be used for some gentle security in a residential setting, so those defacto, bright white, LED lights are not really appropriate in such a setting. It would be used to replace the current ionized gas (sodium vapor) amber lights that use a ballast, etc), so the maintenance issues would be negligible, unlike the current one. |
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#2
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OT - outdoor amber LED flood lights?
Bill in Co wrote:
I know this is completely OT, but I was just wondering if anyone has ever been able to find any outdoor, dusk to dawn, amber colored LED flood lights (and fixtures), as I can't seem to find any listed anywhere. They would be used for some gentle security in a residential setting, so those defacto, bright white, LED lights are not really appropriate in such a setting. It would be used to replace the current ionized gas (sodium vapor) amber lights that use a ballast, etc), so the maintenance issues would be negligible, unlike the current one. You probably need "yellow" instead of "amber" as a search term. Although when I tried Newark after trying Home Depot, both colors were listed. https://www.homedepot.com/p/Philips-...9080/300817717 And you really want to see the product in person. Actual yellow LEDs would be "too pure" of a yellow. You probably want a light which is a "*******ized white". They start with a blue LED (for efficiency and energetic photons), and they use various phosphors to attain other colors. That would be better than "pure yellow". This would be an example of hunting down a yellow LED. These might be 1/3rd the efficiency of blue+phosphor (white) LEDs. https://canada.newark.com/osram-opto...lm/dp/62AC0719 The hard part of working with items like that, is soldering them. It's difficult for a hobbyist to control conditions well enough to deal with them directly. The high power items tend to be surface-mount. The little LEDs have leads that make hobbyist usage a lot easier. But then you'd need $250 worth to make a light bulb (to get it bright enough) :-) Paul |
#3
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OT - outdoor amber LED flood lights?
Bill in Co wrote:
I know this is completely OT, but I was just wondering if anyone has ever been able to find any outdoor, dusk to dawn, amber colored LED flood lights (and fixtures), as I can't seem to find any listed anywhere. They would be used for some gentle security in a residential setting, so those defacto, bright white, LED lights are not really appropriate in such a setting. It would be used to replace the current ionized gas (sodium vapor) amber lights that use a ballast, etc), so the maintenance issues would be negligible, unlike the current one. You might want to call or email LSI. We get all of our industrial LED lighting from them. http://www.lsi-industries.com/ |
#4
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OT - outdoor amber LED flood lights?
In message , Paul
writes: Bill in Co wrote: [] not really appropriate in such a setting. It would be used to replace the current ionized gas (sodium vapor) amber lights that use [] Actual yellow LEDs would be "too pure" of a yellow. You probably want a light which is a "*******ized white". They start with a blue LED (for efficiency and energetic photons), and they use various phosphors to attain other colors. That would be better than "pure yellow". If he's replacing sodium vapour lights, those are pretty close to monochrome! Two Fraunhofer lines very close together in the yellow (with a weak red one, which may be from the neon they contain to get them started). This would be an example of hunting down a yellow LED. These might be 1/3rd the efficiency of blue+phosphor (white) LEDs. Are they, actually? I thought the phosphors were used (a) to translate down the peak emission which is in the UV for those LEDs, (b) to broaden the peak (i. e. give white); I thought the peak for yellow LEDs was actually in the yellow already. Of course it might be that nobody makes high-power yellow ones; the majority of development recently does seem to have been in the white area (using phosphors since LED's emissions are intrinsically fairly narrow-band), and maybe white with a filter may be the only option available. (He did specifically say bright white would _not_ be appropriate [though I wonder if not-so-bright white might be].) [] -- J. P. Gilliver. UMRA: 1960/1985 MB++G()AL-IS-Ch++(p)Ar@T+H+Sh0!:`)DNAf (Petitions - at least e-petitions - should collect votes both for and against, if they're going to be reported as indicative of public opinion. If you agree, please click below, unless you already have.) [UK only] https://petition.parliament.uk/petit...BYobumelL9J54c Veni Vidi Visa [I came, I saw, I did a little shopping] - Mik from S+AS Limited ), 1998 |
#5
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OT - outdoor amber LED flood lights?
J. P. Gilliver (John) wrote:
In message , Paul writes: Bill in Co wrote: [] not really appropriate in such a setting. It would be used to replace the current ionized gas (sodium vapor) amber lights that use [] Actual yellow LEDs would be "too pure" of a yellow. You probably want a light which is a "*******ized white". They start with a blue LED (for efficiency and energetic photons), and they use various phosphors to attain other colors. That would be better than "pure yellow". If he's replacing sodium vapour lights, those are pretty close to monochrome! Two Fraunhofer lines very close together in the yellow (with a weak red one, which may be from the neon they contain to get them started). This would be an example of hunting down a yellow LED. These might be 1/3rd the efficiency of blue+phosphor (white) LEDs. Are they, actually? I thought the phosphors were used (a) to translate down the peak emission which is in the UV for those LEDs, (b) to broaden the peak (i. e. give white); I thought the peak for yellow LEDs was actually in the yellow already. Of course it might be that nobody makes high-power yellow ones; the majority of development recently does seem to have been in the white area (using phosphors since LED's emissions are intrinsically fairly narrow-band), and maybe white with a filter may be the only option available. (He did specifically say bright white would _not_ be appropriate [though I wonder if not-so-bright white might be].) [] They do make them. I have Lumileds documentation here for the color ones, such as yellow, red, green. The efficiency of direct LED output devices varies, as does the sensitivity of the human eye to the colors in question. You've probably seen the red/yellow/green LEDs used for panel indicators. If you use enough of those in an array, it makes an illuminator. The conversion efficiency improves, the more that you can eliminate crystal defects from the structures at the atomic level. Some chemical combinations just don't pack well. And the spectral width on a LED, is somewhere around a couple hundred nanometers. They're not sharp like a laser. (There's a difference between the half-power rating, and the width of the skirt as seen on a lab spectrometer.) The blue LED is nominally blue, with the usual skirt. And then the phosphor converts some of the energy into other colors. There are likely multiple phosphors, mixed together. The more phosphor, the less blue leaks through, but the less efficient they are overall. And the process has a name, like "phosphor smothering". That's why Philips made a generation of bulbs with remote phosphor, the claim being that this was a more efficient phosphor conversion scheme. (Those are the yellow looking bulbs I rejected here, where it said on the package specifically "these are white, not yellow", and the light they gave out was yellowish in a "projection onto kitchen wall" test.) But a warm white bulb still wouldn't meet the "bug light" requirement of the OP. It's possible blue+phosphor would be a more efficient emitter than yellow directly, But then it would be a matter of whether a good phosphor exists for that process or not. There are some neat phosphors, and also some ugly characteristics. Somebody invented a "pink" LED, and whatever process it used, the color shifts in only a couple of days usage. Making the color "useless" from a design perspective. If your application needed a constant pink, you would not get it from the "prototype" version of those. So what would be happening there, is likely a chemical reaction (breakdown) fueled by energetic photons. And they do make ultraviolet illuminators, which can be used for applications like polymerizing the liquid in dental filling plastic. But those LEDs are expensive, presumably in an attempt to convince people to not buy them for innocent home experiments. I don't think those are all that safe. ******* https://en.wikipedia.org/wiki/Light-emitting_diode "The wavelength of the light emitted, and thus its color, depends on the band gap energy of the materials forming the p-n junction. The materials used for the LED have a direct band gap with energies corresponding to near-infrared, visible, or near-ultraviolet light. eff lm/W (IR 760 λ ) Red 620 λ 645 0.39 72 Red-orange 610 λ 620 0.29 98 (Yellow 570 λ 590) Green 520 λ 550 0.15 93 Cyan 490 λ 520 0.26 75 Blue 460 λ 490 0.35 37 === can be converted to white ... (UV "down to 210 nm") " The red has nice efficiency, but makes an unpleasant illuminator. It might be good for your dark room though (when developing film). The price of the LEDs has come down, but the ability to use them has got worse with time. As they're SMT and a PITA to work with. Even if you buy the large (1" array or larger), those have a lot of heat output, and the heatsink costs more than the LED :-) They're making them with silicon carbide now, to take more heat, but I'm still not comfortable with cooking them. The light bulb manufacturers don't mind doing that. This is the form factor I used here. My kitchen lighting is two of these. The substrate is fastened to a heatsink with screws and epoxy. (The epoxy being necessary because the substrates "slide around" a bit without something to help the screws.) The light bounces off the ceiling, because you don't really want to look into these. And this is subdued lighting, not sufficient for reading a newspaper. But you can leave them running all day if you want. They don't use a lot of power. https://en.wikipedia.org/wiki/File:2...,_Lumiled).jpg That form factor helps with SMT LEDs, as you get solder pads a hobbyist can use. The boring part, is making a DC power source (a current source) if you work with LEDs in home projects. I used an LM317 to make a current source for my project, which is far from efficient. Circuits don't get much simpler than this :-) https://i.stack.imgur.com/qumNL.png Paul |
#6
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OT - outdoor amber LED flood lights?
In message , Paul
writes: J. P. Gilliver (John) wrote: In message , Paul writes: Bill in Co wrote: [] not really appropriate in such a setting. It would be used to replace the current ionized gas (sodium vapor) amber lights that use [] Actual yellow LEDs would be "too pure" of a yellow. You probably want a light which is a "*******ized white". They start with a blue LED (for efficiency and energetic photons), and they use various phosphors to attain other colors. That would be better than "pure yellow". If he's replacing sodium vapour lights, those are pretty close to monochrome! Two Fraunhofer lines very close together in the yellow (with a weak red one, which may be from the neon they contain to get them started). This would be an example of hunting down a yellow LED. These might be 1/3rd the efficiency of blue+phosphor (white) LEDs. Are they, actually? I thought the phosphors were used (a) to translate down the peak emission which is in the UV for those LEDs, (b) to broaden the peak (i. e. give white); I thought the peak for yellow LEDs was actually in the yellow already. Of course it might be that nobody makes high-power yellow ones; the majority of development recently does seem to have been in the white area (using phosphors since LED's emissions are intrinsically fairly narrow-band), and maybe white with a filter may be the only option available. (He did specifically say bright white would _not_ be appropriate [though I wonder if not-so-bright white might be].) [] They do make them. I have Lumileds documentation here for the color ones, such as yellow, red, green. The efficiency of direct LED output devices varies, as does the sensitivity of the human eye to the colors in question. I think it (the human sensitivity) peaks around yellow-green. You've probably seen the red/yellow/green LEDs used for panel indicators. If you use enough of those in an array, it makes an illuminator. The conversion efficiency improves, the I worked in electronics for a third of a century, though I'll admit I didn't get much involved with LEDs much beyond the _arrival_ of blue ones. more that you can eliminate crystal defects from the structures at the atomic level. Some chemical combinations just don't pack well. And the spectral width on a LED, is somewhere around a couple hundred nanometers. They're not sharp like a laser. (There's a difference between the half-power rating, and the width of the skirt as seen on a lab spectrometer.) Yes, so Bill's requirement - "gentle security" as he put it - _would_, I think, be satisfied by "genuine" yellow LEDs, rather than phosphor ones. (After all, if the residents have been happy with sodium ones ...!) The blue LED is nominally blue, with the usual skirt. And then the phosphor converts some of the energy into other colors. There are likely multiple phosphors, mixed together. The more phosphor, the less blue leaks through, but the less efficient they are overall. And the process has a name, like "phosphor smothering". It was my understanding that when the holy grail of the "white LED" was originally developed, it used an LED that was very much at the blue/UV end, with a fair proportion of the skirt beyond the visible spectrum, and brought back into it by the phosphors (as you say, probably a mixture, to make the output "white"). Much like fluorescent tubes (which use a discharge - spark - that's mostly outside the visible; I don't know what the gas they use is). That's why Philips made a generation of bulbs with remote phosphor, the claim being that this was a more efficient Like the second-generation Sinclair portable TV, which had a side-firing electron gun deflected into the phosphor and viewed from that side. phosphor conversion scheme. (Those are the yellow looking bulbs I rejected here, where it said on the package specifically "these are white, not yellow", and the light they gave out was yellowish in a "projection onto kitchen wall" test.) But a warm white bulb still wouldn't meet the "bug light" requirement of the OP. I've re-read his original post - "gentle security"; he doesn't mention bugs (-: It's possible blue+phosphor would be a more efficient emitter than yellow directly, But then it would be a matter of whether a good phosphor exists for that process or not. There are some neat phosphors, and also some ugly characteristics. Somebody invented a "pink" LED, and whatever process it used, the color shifts in only a couple of days usage. Making the color "useless" from a design perspective. If your application Ah, I wondered what happened to those! So they don't stay pink, do they not! [] And they do make ultraviolet illuminators, which can be used for applications like polymerizing the liquid in dental filling plastic. But those LEDs are expensive, presumably in an attempt to convince people to not buy them for innocent home experiments. I don't think those are all that safe. I wonder if you could make some by cutting the phosphor off some "white" ones (-:! [Much like, way back in the days of germanium transistors, you could - so I'm told - make the much more expensive OCP71 phototransistor by scraping some of the paint off the ordinary OC71 transistor!] [] "The wavelength of the light emitted, and thus its color, depends on the band gap energy of the materials forming the p-n junction. The materials used for the LED have a direct band gap with energies corresponding to near-infrared, visible, or near-ultraviolet light. eff lm/W (IR 760 0 Red 620 0 Red-orange 610 0 (Yellow 570 0 Green 520 0 Cyan 490 0 Blue 460 0 ... (UV "down to 210 nm") " I notice they've omitted the efficiency figure for the yellow (and UV) ones! The red has nice efficiency, but makes an unpleasant illuminator. It might be good for your dark room though (when developing film). If anyone still does (-:. The price of the LEDs has come down, but the ability to use them has got worse with time. As they're SMT and a PITA to work with. Even if you buy the large (1" array or larger), those have a lot of heat output, and the heatsink costs more than the LED :-) They're making them with silicon carbide now, to take more heat, but I'm still not comfortable with cooking them. The light bulb manufacturers don't mind doing that. When blue first came out, I understood they used silicon carbide to get the necessary band-gap, rather than any heat-resistant property (though I've no doubt that is useful). I remember the first blue ones had a Vf of getting on for 5 volts, rather than 1.8 for red and about 2.2 for green/yellow. [] The boring part, is making a DC power source (a current source) if you work with LEDs in home projects. I used an LM317 to make a current source for my project, which is far from efficient. Circuits don't get much simpler than this :-) [] I agree, not so hot (!) on the efficiency front. I think a lot of LED assemblies use multiple chips and a voltage source, with a low-value resistor to limit the current a bit. Such as the plug-in replacements they sell for car tail lights (for older cars that are designed for filament bulbs) - these obviously use several LED chips in series. [Interestingly, they seem only to sell those in "white", whereas you'd have thought red (brake, tail) or yellow/orange (indicator) would suit better; I guess efficiency's not too much of a concern there, and they just rely on the coloured housing as they did anyway with the filament bulb. Thus getting economies of scale, rather than having to stock all the colours.] -- J. P. Gilliver. UMRA: 1960/1985 MB++G()AL-IS-Ch++(p)Ar@T+H+Sh0!:`)DNAf (Petitions - at least e-petitions - should collect votes both for and against, if they're going to be reported as indicative of public opinion. If you agree, please click below, unless you already have.) https://petition.parliament.uk/petit...n=gHafDVBYobum elL9J54c "To YOU I'm an atheist; to God, I'm the Loyal Opposition." - Woody Allen |
#7
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OT - outdoor amber LED flood lights?
J. P. Gilliver (John) wrote:
In message , Paul writes: J. P. Gilliver (John) wrote: In message , Paul writes: Bill in Co wrote: [] not really appropriate in such a setting. It would be used to replace the current ionized gas (sodium vapor) amber lights that use [] Actual yellow LEDs would be "too pure" of a yellow. You probably want a light which is a "*******ized white". They start with a blue LED (for efficiency and energetic photons), and they use various phosphors to attain other colors. That would be better than "pure yellow". If he's replacing sodium vapour lights, those are pretty close to monochrome! Two Fraunhofer lines very close together in the yellow (with a weak red one, which may be from the neon they contain to get them started). This would be an example of hunting down a yellow LED. These might be 1/3rd the efficiency of blue+phosphor (white) LEDs. Are they, actually? I thought the phosphors were used (a) to translate down the peak emission which is in the UV for those LEDs, (b) to broaden the peak (i. e. give white); I thought the peak for yellow LEDs was actually in the yellow already. Of course it might be that nobody makes high-power yellow ones; the majority of development recently does seem to have been in the white area (using phosphors since LED's emissions are intrinsically fairly narrow-band), and maybe white with a filter may be the only option available. (He did specifically say bright white would _not_ be appropriate [though I wonder if not-so-bright white might be].) [] They do make them. I have Lumileds documentation here for the color ones, such as yellow, red, green. The efficiency of direct LED output devices varies, as does the sensitivity of the human eye to the colors in question. I think it (the human sensitivity) peaks around yellow-green. You've probably seen the red/yellow/green LEDs used for panel indicators. If you use enough of those in an array, it makes an illuminator. The conversion efficiency improves, the I worked in electronics for a third of a century, though I'll admit I didn't get much involved with LEDs much beyond the _arrival_ of blue ones. more that you can eliminate crystal defects from the structures at the atomic level. Some chemical combinations just don't pack well. And the spectral width on a LED, is somewhere around a couple hundred nanometers. They're not sharp like a laser. (There's a difference between the half-power rating, and the width of the skirt as seen on a lab spectrometer.) Yes, so Bill's requirement - "gentle security" as he put it - _would_, I think, be satisfied by "genuine" yellow LEDs, rather than phosphor ones. (After all, if the residents have been happy with sodium ones ...!) The blue LED is nominally blue, with the usual skirt. And then the phosphor converts some of the energy into other colors. There are likely multiple phosphors, mixed together. The more phosphor, the less blue leaks through, but the less efficient they are overall. And the process has a name, like "phosphor smothering". It was my understanding that when the holy grail of the "white LED" was originally developed, it used an LED that was very much at the blue/UV end, with a fair proportion of the skirt beyond the visible spectrum, and brought back into it by the phosphors (as you say, probably a mixture, to make the output "white"). Much like fluorescent tubes (which use a discharge - spark - that's mostly outside the visible; I don't know what the gas they use is). That's why Philips made a generation of bulbs with remote phosphor, the claim being that this was a more efficient Like the second-generation Sinclair portable TV, which had a side-firing electron gun deflected into the phosphor and viewed from that side. phosphor conversion scheme. (Those are the yellow looking bulbs I rejected here, where it said on the package specifically "these are white, not yellow", and the light they gave out was yellowish in a "projection onto kitchen wall" test.) But a warm white bulb still wouldn't meet the "bug light" requirement of the OP. I've re-read his original post - "gentle security"; he doesn't mention bugs (-: It's possible blue+phosphor would be a more efficient emitter than yellow directly, But then it would be a matter of whether a good phosphor exists for that process or not. There are some neat phosphors, and also some ugly characteristics. Somebody invented a "pink" LED, and whatever process it used, the color shifts in only a couple of days usage. Making the color "useless" from a design perspective. If your application Ah, I wondered what happened to those! So they don't stay pink, do they not! [] And they do make ultraviolet illuminators, which can be used for applications like polymerizing the liquid in dental filling plastic. But those LEDs are expensive, presumably in an attempt to convince people to not buy them for innocent home experiments. I don't think those are all that safe. I wonder if you could make some by cutting the phosphor off some "white" ones (-:! [Much like, way back in the days of germanium transistors, you could - so I'm told - make the much more expensive OCP71 phototransistor by scraping some of the paint off the ordinary OC71 transistor!] [] "The wavelength of the light emitted, and thus its color, depends on the band gap energy of the materials forming the p-n junction. The materials used for the LED have a direct band gap with energies corresponding to near-infrared, visible, or near-ultraviolet light. eff lm/W (IR 760 0 Red 620 0 Red-orange 610 0 (Yellow 570 0 Green 520 0 Cyan 490 0 Blue 460 0 ... (UV "down to 210 nm") " I notice they've omitted the efficiency figure for the yellow (and UV) ones! The red has nice efficiency, but makes an unpleasant illuminator. It might be good for your dark room though (when developing film). If anyone still does (-:. The price of the LEDs has come down, but the ability to use them has got worse with time. As they're SMT and a PITA to work with. Even if you buy the large (1" array or larger), those have a lot of heat output, and the heatsink costs more than the LED :-) They're making them with silicon carbide now, to take more heat, but I'm still not comfortable with cooking them. The light bulb manufacturers don't mind doing that. When blue first came out, I understood they used silicon carbide to get the necessary band-gap, rather than any heat-resistant property (though I've no doubt that is useful). I remember the first blue ones had a Vf of getting on for 5 volts, rather than 1.8 for red and about 2.2 for green/yellow. [] The boring part, is making a DC power source (a current source) if you work with LEDs in home projects. I used an LM317 to make a current source for my project, which is far from efficient. Circuits don't get much simpler than this :-) [] I agree, not so hot (!) on the efficiency front. I think a lot of LED assemblies use multiple chips and a voltage source, with a low-value resistor to limit the current a bit. Such as the plug-in replacements they sell for car tail lights (for older cars that are designed for filament bulbs) - these obviously use several LED chips in series. [Interestingly, they seem only to sell those in "white", whereas you'd have thought red (brake, tail) or yellow/orange (indicator) would suit better; I guess efficiency's not too much of a concern there, and they just rely on the coloured housing as they did anyway with the filament bulb. Thus getting economies of scale, rather than having to stock all the colours.] To clarify any ambiguities, this item would be used to replace an existing HID high pressure sodium light assembly that gives off a pleasing amber light, so that any bedrooms exposed to such see just that, and NOT that obnoxious WHITE light coming out of these LED light assemblies. No, I don't think I mentioned bug lights, or if I did, it would have been in the context of getting that kind of toned down color, that's all. I could add a comment about some of the LED automobile headlights these days too, but I'll refrain here, as it's pretty obvious too - for the same reasons. But I do understand why it's being done (in both cases), since the LED's have a really great lifetime, and need much less servicing. But it sure sucks to see it. But for high security purposes I definitely think it fits the bill - but that's it. The problem seems to be being able to develop a better and practical LED assembly with these nice, toned down, amber colors, just like those HID sodium vapor ones put out, at least for these specific situations. Time will tell if we ever get there, or if there is enough demand for such. |
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